This invention relates to the separation of the isotopes of zirconium predominantly for the fabrication of parts or components of a nuclear reactor. The invention has particular relationship to the separation of the zirconium isotopes by irradiating vapor of a zirconium-containing compound with a laser beam tuned to the component of the selected isotope and to the discovery of a compound uniquely suitable for such separation. An isotope of zirconium which is selected for separation is herein generally designated S.sub.Zr.
Feichtner teaches the separation of isotopes by laser irradiation of certain zirconium alkoxides. It has been found that while such alkoxides have properties which are uniquely suitable for the separation process, they are subject to hydrolysis and their processing requires precautions against hydrolysis. Nadalin teaches the use for isotope separation of the dicyclopentadienyl zirconium alkoxide compounds dicyclopentadienyl zirconium dichloride, (herein DZD), dicyclopentadienyl zirconium diisopropoxide (herein DZDI) and dicyclopentadienyl zirconium-di-tert-butoxide (herein DZDB). These compounds are not at all or are less subject to hydrolysis than the tetra alkoxides of zirconium disclosed in Feichtner. The DZD is available commercially or is readily prepared from zirconium tetrachloride. However, for isotope separation, DZD has the disadvantage that it includes chlorine. Chlorine has isotopes .sup.35 Cl, whose abundance is about 75.4% and .sup.37 Cl, whose abundance is about 24.6%. The chlorine isotopes militate against the effective separation of the zirconium isotopes. DZD serves as a starting material for the preparation of DZDI and DZDB which do not include chlorine and can serve for the effective separation of zirconium isotopes. However, difficulty is involved in preparing and purifying the DZDI and the DZDB. The yield of pure DZDI or DZDB in the preparation of these compounds from DZD is only about 10-15%. The cost of preparing these compounds is high.
It is an object of this invention to overcome the above-described disadvantage of the dicyclopentadienyl alkoxides and to provide a volatile zirconium compound suitable for use in the separation of zirconium isotopes which compound can be prepared in substantial quantities with high purity and at relatively low cost.